January has been glaucoma awareness month. I didn’t know this until I was researching the latest information on the disease and noticed it on an “awareness month” list. Glaucoma is a serious medical condition in that it is the second most common cause of blindness in the U.S. Cataracts are the leading cause.
Glaucoma is an eye disorder wherein the pressure inside the eyeball gets too high. This elevated pressure, called intraocular pressure (IOP), can eventually lead to damage of the main nerve of sight, the optic nerve. In its chronic and most common form, it is an essentially silent and progressive disease until the pressure has caused significant damage to the nerve.
There are two main anatomical sections of the eyeball. The posterior chamber is behind the lens of the eye and the anterior chamber lies in front of the lens and iris. The anterior chamber is filled with a watery liquid called the aqueous humor. This fluid is made in the posterior chamber and flows around the lens, through the pupil, and into the anterior chamber where it drains out a mesh-like structure.
In glaucoma, the fluid does not drain quickly enough in the anterior chamber. Because of this, the pressure rises. In most cases this rise in pressure occurs very slowly, over years, and can be undetected until damage has occurred within the eyeball. In its early stages, glaucoma is a symptom-less and painless disease. It usually involves both eyes.
In a few situations the rise in pressure is sudden or acute. This is an emergency and is called acute angle or narrow angle glaucoma. Trauma to the eye, chemical injury, inflammatory conditions and severe eye infections can all lead to the development of glaucoma, though these situations are less common. Some individuals are born with the disease, called congenital glaucoma.
Glaucoma runs in families. It is also more common in those over 40 years of age, African-Americans, those with diabetes and those on long-term steroid medications.
As the disease progresses, the first indication may be a loss of peripheral or side vision. Other symptoms of late disease include tunnel vision, redness in the eyes, seeing halos around lights, haziness of the eyes and pain in the eyes.
Glaucoma is diagnosed by a procedure called tonometry. During the eye exam, the eye doctor applies a probe or a puff of air to the cornea and the pressure inside the eyeball can be obtained. Glaucoma testing is quick and painless.
Treatment for glaucoma is aimed at lowering the intraocular pressure. This may be accomplished through the use of medications (eye drops), laser treatment or microsurgery. These measures either reduce the production of the fluid in the eye or increase its drainage out of the eye.
Since glaucoma cannot be prevented and the damage caused by the disease cannot be reversed, it is important to diagnose the condition as early as possible. This is why regular eye exams are recommended for all, especially if you have a family history of glaucoma or other risk factors for the disease as mentioned above.
The content in this column is for informational purposes only. Consult your physician for appropriate individual treatment. Reynolds practices Family Medicine in Chesterfield.